Quick URL Search от nevernight

A simple and efficient Firefox addon that lets you search across multiple search engines without changing your browser’s default settings.

How to use:
In the URL bar, type s + <search engine> <your query>, and get instant results.

Supports 47 search engines, including Google, Bing, DuckDuckGo, ChatGPT, YouTube, Wikipedia, Reddit, GitHub, TikTok, and many more.

API issue
Unlike Microsoft Edge, where you could type a domain name and a query, Firefox does not provide API access to modify search behavior directly. Instead, this addon uses a simple s command for quick and efficient searches.